Security company F-Secure has discovered a Trojan that is specifically targeting Skype users.

The malware uses social-engineering techniques that play on people’s fears about their PCs becoming infected; it is disguised as a security plug-in calling itself Skype Defender.

If downloaded and executed, the Trojan steals the victim’s Skype log-in details giving the hackers open access to the compromised internet telephony account.

F-Secure’s labs team has posted a blog giving details of the Trojan along with images showing how it tricks people into giving up their Skype log-in details.

Sean Sullivan, senior researcher at the labs, said: “It sounds like a security plug-in, making it particularly dangerous."

F-Secure has added detection for the malware to its security products.